Asteroid Gault is self-destructing.
Images shot by the Hubble Space Telescope show the space rock — some 2.5 to 5.5 miles wide — has left telltale streaks of debris as it hurtles through our solar system. It’s gradually breaking apart.
Why? Sunlight heats up the surface of asteroids, and when enough heat radiates off the rocky body’s surface, this can propel the asteroid and force it to spin. With enough motion, shifting rubble and landslides on the massive rock can tumble into space. Basically, the asteroid is shedding.
Today, telescopes on Earth and in space (like the 29-year-old Hubble) can combine their observations to detect these rarely-seen events.
“Active and unstable asteroids such as Gault are only now being detected by means of new survey telescopes that scan the entire sky, which means asteroids such as Gault that are misbehaving cannot escape detection any more,” Olivier Hainaut, a European Southern Observatory astronomer, said in a statement.
Each of the streaks in the above photo are from separate disintegration events, wherein chunks, soil, and dust from Gault plunged into the solar system.
Astronomers suspect the first mass tumbled into space on Oct. 28, 2018, followed by another release of space rock on December 30th.
Gault, one of some 800,000 known-asteroids in the solar system’s asteroid belt, completes a spin every two hours. That’s enough to destabilize it and make the asteroid prone to landslides. All it needs is just a little nudge.
“Even a tiny disturbance, like a small impact from a pebble, might have triggered the recent outbursts,” University of Hawaii astronomer Jan Kleyna said in a statement.